Derricks



y 1967 H. E. GJELSTEEN 3,317,057

DERRICKS Filed Feb. 18, 1966 2 Sheets-Sheet 1 INVENTOR;

HHNS E. GJELSTEEN y 1967 H. E. GJELSTEEN 3,317,057

DERRICKS Filed Feb. 18, 1966 2 Sheets-Sheet 2- United States Patent 4 Claims. (Cl. 212-58) This invention relates to derricks and, in particular, derricks which are capable of handling two different loads. By the term derrick in this specification is meant any apparatus which can be used for lifting weights, whether on ships or on land.

On cargo boats it is clearly desirable to be able to lift loads heavier than those for which a conventional derrick is intended. Certain ships have been provided with special heavy load booms, but these have to stand unused in the raised position for long periods at a time. While booms are known employing a second loading means suspended at a shorter distance from the inner end of the boom than the normal loading means and serving to raise and lower the heavier loads, their construction and operation has left much to be desired.

It is an object of the present invention to provide a simpler and more advantageous construction for a derrick capable of handling two different loads.

According to the present invention a derrick arrangement comprises a boom having suspended at its outermost end a loading means and, at a distance inwards of said outermost end, another loading means, both loading means being rigged with respective loading lines which are guided therefrom to separate winch means via a common top rope block and means associated with each loading means forlifting the boom by direct engagement therewith, the arrangement being such that one winch can be used as a topping winch and the other as a loading winch and vice-versa.

Conveniently, each lifting means constitutes a stop element formed integrally with the loading means and adapted to bear against a corresponding stop on the boom.

In a preferred form of the invention, the top rope block is connected at one end to a hinge pivotably mounted on the supporting column while the other end is connected by tension bars to a forked bolt about which the lower end of the boom pivots in a vertical plane, said forked bolt, in turn, being mounted adjacent the column to permit the boom to pivot also in a horizontal plane and said top rope block and said tension bars both being pivotable in a vertical plane, the arrangement such that when the boom is raised or lowered the loading means can be guided substantially horizontally.

In this way, the pressure of the boom against the boom pin about which the forked bolt pivots and the tilting moments on the suspension of the top rope block are reduced. Even though this feature is more important for booms capable of handling two loads, it can, of course, also be used for single load booms.

In order that the invention can be more clearly understood, a convenient embodiment thereof will now be described, by way of example, with reference to the accompanying drawings in which:

FIGURE 1 is a schematic side view of a derrick arrangement showing one mode of use, and

FIGURE 2 is a view corresponding to FIGURE 1 showing the arrangement when used in an alternative manner.

In the drawings, there is shown a mast or crane column 1 having a boom or crane beam 2 which is mounted, for pivotal movement in the vertical plane, on a boom forked "ice bolt 3, which in turn is mounted in a boom pin 3a or other device which permits the boom or beam 2 to pivot in the horizontal plane. The arrangement which is used to pivot the boom 2 backwards and forwards and to be locked at a definite angular position, is excluded for the sake of simplicity, since it does not play any role in the invention and can in itself be of known construction.

On the outermost of the boom or the beam 2, there is suspended a loading hook 4 for normal loads and this can be suspended by, for example, a single covered rope 5 which is led over a pulley 6 at the outer end of the boom or beam and to a top rope block 7, where it is led over a pulley 8 and further down over a guide pulley 9 on to a normal loading winch 10.

If this is desired, the loading hook 4 can, if required, be suspended in a loading block having several pulleys, but this will mean, in that case, several pulleys in the mast and in the top rope block.

The loading hook 4 is provided at the top with a stop plate 11 which, on sufficiently drawing in the covered cable 5 on the winch drum, will bear against a stop 12 on the under side of the boom or the crane beam 2, and on continued drawing it will lift (top) this boom or crane beam.

A leading hook or loading block 13 for heavier loads is suspended at a suitable distance further in on the boom or crane beam 2. The associated covered cable 14 is led over guide pulleys 15 and further over pulleys 16, 17 in the top rope block, and its one end is secured at a fixed point 18 on the boom or crane beam 2 and its other end is led over a guide pulley 19 to another winch 20.

The number of pulleys in the loading block 13, the boom and the top rope block can of course be varied, all according to the loading power which is desired.

The loading block 13 is provided with a stop plate 21 which, on drawing in the covered cable 14, will bear against a stop 22 on the under side of the boom or the crane beam 2, and on continued drawing it will lift (top) this boom or crane beam.

It will be evident from this that, when the boom or the crane beam 2 is suspended by the covered cable 5 for the outer loading hook 4, as shown in FIG. 1, the loading block or the loading hook 13 can be used to raise or lower cargo by means of the winch 20, while, with cargo on the loading block 13, the boom or crane beam 2 can be raised or lowered by means of the winch 10 and the associated covered cable 5. The winch 10 can then be used as a topping winch, While the winch 20 is used as a loading winch. One can also, as is shown in FIG. 2, allow the boom or crane beam 2 to be suspended by the covered cable 14 with the loading block 13, while cargo is raised and lowered with the loading book 4, the covered cable 5 and the winch 10, at the same time as the winch 20 is used as a topping winch to raise and lower the boom or crane beam 2 by means of the covered cable 14.

This construction is especially advantageous for cargo boats, where for heavy loads troublesome preparations must often be undertaken with the rigging of a heavy loads boom, which, for the most part of the time, would otherwise stand fixed and unused in the raised position. In practice, the outer hook 4 will be used as a rule for normal loading and unloading, while the loading block 13 and the associated covered cable 14 and the winch 20 is used for topping. The handling of a heavy load is etfected quite simply in that the covered cable 5 is drawn in until the stop plate 11 rests against the stop 12, whereupon the loading block 13 is lowered and is used for lifting.

Another feature of the arrangement according to the invention consists in that the top rope block 7 is connected to the boom forked bolt 3 by tie bars 23, and in that a pivot bolt 24 forms a mounting for a pivotable top rope hinge 25, whereby the connections between the top rope hinge 25 and the top rope block 7, between the top rope block 7 and the tie bars 23, and between the tie bars 23 and the boom forked bolt 3, are all rotatable in the vertical plane. In suitably chosen inclined positions for the top rope block 7 and the bars 23, it can be ensured that these are never strained by other than tension forces at the horizontal boom or crane beam. Since still further these tension forces always have the same direction, irrespective of the angle of the boom with the horizontal plane, the top rope hinge 25 with its pivot bolt 24 is balanced for large tilting moments and the tension forces in the bars 23 reduce the boom pressure against the boom pin or the boom pivot arrangement. These advantages are especially prominent with a high topped boom or crane beam, where these tilting moments and boom pressures would otherwise be especially large. As mentioned earlier this arrangement can also be used with advantage for single loading booms.

Furthermore, an important advantage which is obtained by means of the afore-mentioned feature is that the guidance of both covered wires and 14 can be arranged in a constructively simple manner so that there is achieved a very good approximately horizontal guidance for both loads on topping of the boom or crane beam 2, which makes it simpler to place or carry the cargo anywhere within the range of the boom.

What I claim is:

1. In a derrick arrangement comprising an upright column, a boom, means supporting said boom at its innermost end on said column for pivotal movement in both a horizontal plane and a vertical plane, means operable to pivot and lock said boom in a definite angular orientation, first loading means suspended at the outermost end of said boom, second loading means suspended a distance inwardly of the outermost end of said boom, a pair of winch means and respective loading lines each connecting a respective winch means to a respective loading means; the improvement comprising a common block mounted on said column above said winch means; said loading means being permanently rigged with their respective loading lines and both of said loading lines passing through said common block to their respective winch means; and respective lift means, each associated with a respective loading means and operable directly to engage and lift said boom; whereby either winch means can be used as a topping win-ch and the other used as a loading winch.

2. In a derrick arrangement according to claim 1, a hinge pivotally mounted on said column for pivoting about an axis substantially parallel to said column, said block being connected at one end to said hinge; said means supporting said boom at its innermost end on said column for pivotal movement in a vertical plane comprising a forked bolt mounted adjacent said column for pivotal movement about an axis substantially parallel to said column; and tension bars connecting the outer end of said block to said forked bolt; whereby said boom is pivotal in a horizontal plane and said block and said tension bars are pivotal in a vertical plane; the arrangement being such that, when said boom is raised or lowered, said loading means will remain in substantially the same horizontal plane.

3. In a derrick arrangement according to claim 1, wherein each lifting means constituting a stop element formed integrally with the respective loading means and adapted to bear against a respective corresponding stop on the boom.

4. An arrangement according to claim 2 having a single loading means and associated loading line and winch means.

References Cited by the Examiner UNITED STATES PATENTS 1/ 1924 Cochran 2 1 25 9 4/ 1940 Schroeder 21259 

1. IN A DERRICK ARRANGEMENT COMPRISING AN UPRIGHT COLUMN, A BOOM, MEANS SUPPORTING SAID BOOM AT ITS INNERMOST END ON SAID COLUMN FOR PIVOTAL MOVEMENT IN BOTH A HORIZONTAL PLANE AND A VERTICAL PLANE, MEANS OPERABLE TO PIVOT AND LOCK SAID BOOM IN A DEFINITE ANGULAR ORIENTATION, FIRST LOADING MEANS SUSPENDED AT THE OUTERMOST END OF SAID BOOM, SECOND LOADING MEANS SUSPENDED A DISTANCE INWARDLY OF THE OUTERMOST END OF SAID BOOM, A PAIR OF WINCH MEANS AND RESPECTIVE LOADING LINES EACH CONNECTING A RESPECTIVE WINCH MEANS TO A RESPECTIVE LOADING MEANS; THE IMPROVEMENT COMPRISING A COMMON BLOCK MOUNTED ON SAID COLUMN ABOVE SAID WINCH MEANS; SAID LOADING MEANS BEING PERMANENTLY RIGGED WITH THEIR RESPECTIVE LOADING LINES AND BOTH OF SAID LOADING LINES PASS- 